1. Field of Invention
This invention relates to seatbelt systems and more particularly to seatbelt systems which automatically fasten and unfasten the passenger restraining belt about the passenger after he has seated himself.
2. Prior Art
Since seatbelt systems protect passengers by restraining them with a belt during vehicular emergencies, passengers in the vehicles do not collide with dangerous objects and their safety is insured. However, for reasons such as the difficulty of fastening the restraining belt, etc. the proportion of wearers of seatbelts is very low.
For this reason, passive seatbelt systems which automatically fasten the restraining belt about the passenger after he has seated himself have been proposed. These seabelt systems have a guide rail provided in or on the car body and the belt is caused to approach or move away from the seated passenger to permit automatic fastening or unfastening of the belt by means of a runner piece to which the end of the belt is attached and which is caused to move along the guide rail.
However, the runner pieces are usually connected to the guide rail by wheels and the runner piece usually includes several wheels to minimize resistance to the motion of the runner piece and make motion of the runner piece smooth. As a result of the plurality of wheels utilized by the runner piece, the external form of the runner piece and the guide rail is enlarged and forms a substantial projection into the interior of the motor vehicle. This condition is aggravated by the requirement of a strong runner piece. However, if the guide rail and runner piece are designed so that the runner piece slides directly in the guide rail to reduce the size, the smooth operation of the runner piece is impaired and comfortable and reliable automatic fastening of the belt is not afforded.